After two years of testing DNSSEC, Comcast — the largest provider of cable services in the U.S., with 23.6 million cable customers, 15.9 million high-speed Internet customers and 7.6 million voice customers  — announced it is starting a trial today and plans to implement DNSSEC by the first quarter of 2011 or sooner.  In a blog post, Comcast noted:  

We plan to implement DNSSEC for the websites we manage, such as comcast.com, comcast.net and xfinity.com, by the first quarter of 2011, if not sooner. By the end of 2011, we plan to implement DNSSEC validation for all of our customers….If you don’t want to wait until 2011, you can participate in our DNSSEC customer trial, which starts today. Opt-in by changing your DNS server IP addresses to 75.75.75.75 and 75.75.76.76 (we’ll be adding IPv6 addresses soon). The servers supporting this are deployed nationally in the same locations as our other DNS servers that millions of customers use everyday.

You can find FAQs on the Comcast trial here.